Sealing gasket



Patented Apr. 26, 1927.

UNITED STATES- THEODORE J. SNYDER, OF CHICAGO, ILLINOIS.

SEALING GASKET.

Application filed May 14, 1925. Serial No. 30,260.

My invention relates to sealing gaskets or packing rings in conjunction with parts or members which are placed with the aid thereof in sealed assembly.

In carrying out my invention the gasket or packing ring is desirably made of rubber and there is an annular cavity in at least one engaging face of the ring which furnishes suction when the members between which the packing ring is interposed are clamped in assembly against the ring. lVhen it is desired to break the seal afforded by the ring a simple prying tool may be inserted between the ring and one of the members engaging it to afford communication between the cavity and the external air. In the preferred embodiment of theinvention there are two such cavities one in each engaging face of the ring and in order that the ring may not be unduly thick and for the purpose of making the ring more adaptable to the space between the members engaging it, one of these annular cavities is within the circle of the other.

The invention will be more fully explained in connectionwith the accompanying drawing in which Fig. 1 is a vertical section of the upper portion of a Mason fruit jar with the packing ring of my invention in place between the cover and shoulder of the jar; Fig. 2 is a sectional view of the preferred form of ring showing its shape when not in place; Fig. 3 is a top view of the ring and Fig. 4 shows a part of the structure as it is illustrated in Fig. 1

illustrating the use of a prying tool to establish a vent between one of the annular cavities and the external air. I have shown my invention as being employed in connection with a Mason fruit jar in which the upper part 1 is illustrated on a large scale. This jar has the usual exteriorly threaded neck 2 surrounded by a shoulder 3. The jar is usually of glass. The closure cap 4 for the jar is usually of metal and its skirt is threaded so that it may be screwed on to the jar neck. The cap has abase portion in the nature of a flange 5, which overlaps the shoulder 3. The packing ring 6 preferably of the shape illustrated in Fig. 2 is clamped between the base portion 5 of the cap and the shoulder 3 of the jar, this clamping being efiected by screwing the cap upon the jar neck to the limit permitted by the gasket. The shoulder 3 usually slopes as shown on which account the bottom face of the ring6 also slopes so that this ring face and the top face of the shoulder will have intimate contact throughout except where the sealing annular cavity 7 is provided in this face of the ring. Another sealing annular cavity 8 is provided in the ring, this latter cavity being in the top face of the ring that is engaged by the base portion 5 of the cap. The cavity 7 1s deslrably near the periphery of the ring while the cavity 8 is of smaller diameter than the cavity 7 and is located near the inner edge of the ring, cavity 8 thus being within the circle of the cavity 7. When the cap 18 screwed into place with suficient force the shape of the ring is slightly modified due to the pressure thereon exerted by the clamping action of the cap, the ring adaptlng itself to all inequalities in the surface of the jar shoulder 3 engaged thereby and also be1ng crowded, at its upper and inner port1on, by the cap base into the space between the jar neck and the threaded portion of the cap. The top face of the ring is, consequently, placed into intimate contact throughout the lower surface of the base portion 5 of the cap, except where the cavity 8 occurs, and the inner circular face of thering is also placed in intimate contact with the portion of the jar neck surrounded thereby. The gasket or packing ring thus serves to effect the sealing of the cap and jar in air tight assembly at many points. When it is desired to break the pneumatic seal between the cap and jar, it 18 only necessary to lift an outer portion of the ring, as by means of a prying tool 9, to establish communication between the annular cavity 7 and the external air. If it should happen that this operation fails to break the pneumatic seal at the cavity 8, the prying tool may be inserted between the top side of the ring and the bottom of the cap to assure communication between the cavity 8 and the external atmosphere.

Having thus described my invention I claim:

A jar having an exteriorly threaded neck and a surrounding shoulder at the base of the neck; in combination with a cap threadin a Mason jar ed upon said neck and having a base portion overlying said shoulder; and a packing ring of resilient material clamped by the cap bet-Ween the base portion of the cap and the shoulder of the jar, said" packing ring having an annular cavity in each of its lower and upper faces and respectively closed air tight by the jar shoulder and cap base, the cavity in one face of the ring being Within the circle of the other cavity. 10

In Witness whereof, I hereunto subscribe my name.

THEODORE J. SNYDER. 

